PeakD is the Hive version of Steempeak. I was a hardcore fan of Steempeak since long ago, so I started using PeakD from day 1. I was impressed with how quickly they got everything working right after the fork. They had most bugs fixed within the first day, and they've actually added some features since then.

Ionomy had both Hive and Steem listed on the first day that Hive opened. I've used their exchange to swap whatever liquid Steem I had. They don't have a direct STEEM/HIVE pair, so you have to buy Bitcoin first, then buy the other coin with your Bitcoin. It's also a regular exchange where you can make limit orders and all that, as opposed to a quick swap service like Blocktrades. It might still be a better deal than Blocktrades. The exchange rates at Blocktrades fluctuate quite a bit. One time I checked the rate was 93 HIVE for 100 STEEM, then I checked later the same day and it was at 60 HIVE for 100 STEEM. That's wild.